// 日志器模块：

#ifndef __M_LOGGER_H__
#define __M_LOGGER_H__

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include "util.hpp"
#include "level.hpp"
#include "format.hpp"
#include "sink.hpp"
#include "looper.hpp"
#include <atomic>
#include <cstdarg>

namespace log
{
    class Logger
    {
    public:
        using ptr = std::shared_ptr<Logger>;
        Logger(const std::string &logger_name,
               LogLevel::value level,
               Formatter::ptr &formatter,
               std::vector<LogSink::ptr> &sinks) : _logger_name(logger_name),
                                                   _limit_level(level),
                                                   _formatter(formatter),
                                                   _sinks(sinks.begin(), sinks.end()) {}
        const std::string &name(){return _logger_name;}
        // 构造日志器对象并格式化，得到格式化字符串，进行落地输出
        void debug(const std::string &file, size_t line, const std::string &fmt, ...)
        {
            // 通过传入的对象构造日志器对象并格式化，得到格式化字符串，进行落地输出
            //  1.判断当前日志是否达到输出等级
            if (LogLevel::value::DEBUG < _limit_level)
            {
                return;
            }
            // 2.对fmt格式化字符串和不定参惊醒字符串组织，得到日志信息字符串
            va_list ap;
            va_start(ap, fmt);
            char *res;
            int ret = vasprintf(&res, fmt.c_str(), ap);
            if (ret == -1)
            {
                std::cout << "vasprintf failed!!\n";
                return;
            }
            va_end(ap);
            serialize(LogLevel::value::DEBUG, file, line, res);
            free(res);
        }

        void info(const std::string &file, size_t line, const std::string &fmt, ...)
        {
            // 通过传入的对象构造日志器对象并格式化，得到格式化字符串，进行落地输出
            //  1.判断当前日志是否达到输出等级
            if (LogLevel::value::INFO < _limit_level)
            {
                return;
            }
            // 2.对fmt格式化字符串和不定参惊醒字符串组织，得到日志信息字符串
            va_list ap;
            va_start(ap, fmt);
            char *res;
            int ret = vasprintf(&res, fmt.c_str(), ap);
            if (ret == -1)
            {
                std::cout << "vasprintf failed!!\n";
                return;
            }
            va_end(ap);
            serialize(LogLevel::value::INFO, file, line, res);
            free(res);
        }

        void warn(const std::string &file, size_t line, const std::string &fmt, ...)
        {
            // 通过传入的对象构造日志器对象并格式化，得到格式化字符串，进行落地输出
            //  1.判断当前日志是否达到输出等级
            if (LogLevel::value::WARN < _limit_level)
            {
                return;
            }
            // 2.对fmt格式化字符串和不定参惊醒字符串组织，得到日志信息字符串
            va_list ap;
            va_start(ap, fmt);
            char *res;
            int ret = vasprintf(&res, fmt.c_str(), ap);
            if (ret == -1)
            {
                std::cout << "vasprintf failed!!\n";
                return;
            }
            va_end(ap);
            serialize(LogLevel::value::WARN, file, line, res);
            free(res);
        }

        void error(const std::string &file, size_t line, const std::string &fmt, ...)
        {
            // 通过传入的对象构造日志器对象并格式化，得到格式化字符串，进行落地输出
            //  1.判断当前日志是否达到输出等级
            if (LogLevel::value::ERROR < _limit_level)
            {
                return;
            }
            // 2.对fmt格式化字符串和不定参惊醒字符串组织，得到日志信息字符串
            va_list ap;
            va_start(ap, fmt);
            char *res;
            int ret = vasprintf(&res, fmt.c_str(), ap);
            if (ret == -1)
            {
                std::cout << "vasprintf failed!!\n";
                return;
            }
            va_end(ap);
            serialize(LogLevel::value::ERROR, file, line, res);
            free(res);
        }

        void fatal(const std::string &file, size_t line, const std::string &fmt, ...)
        {
            // 通过传入的对象构造日志器对象并格式化，得到格式化字符串，进行落地输出
            //  1.判断当前日志是否达到输出等级
            if (LogLevel::value::FATAL < _limit_level)
            {
                return;
            }
            // 2.对fmt格式化字符串和不定参惊醒字符串组织，得到日志信息字符串
            va_list ap;
            va_start(ap, fmt);
            char *res;
            int ret = vasprintf(&res, fmt.c_str(), ap);
            if (ret == -1)
            {
                std::cout << "vasprintf failed!!\n";
                return;
            }
            va_end(ap);
            serialize(LogLevel::value::FATAL, file, line, res);
            free(res);
        }

    protected:
        // 封装，避免代码冗余
        void serialize(LogLevel::value level, const std::string &file, size_t line, char *str)
        {
            // 3.构造LogMsg对象
            LogMsg msg(level, line, file, _logger_name, str);
            // 4.通过格式化工具对LogMsg进行格式化，得到格式化后的字符串
            std::stringstream ss;
            _formatter->format(ss, msg);
            // 5.日志落地
            log(ss.str().c_str(), ss.str().size());
        }
        // 抽象接口完成实际的落地输出，不同日志器有不同的落地方式
        virtual void log(const char *data, size_t len) = 0;

    protected:
        std::mutex _mutex;
        std::string _logger_name;
        std::atomic<LogLevel::value> _limit_level;
        Formatter::ptr _formatter;
        std::vector<LogSink::ptr> _sinks;
    };

    class SyncLogger : public Logger
    {
    public:
        SyncLogger(const std::string &logger_name,
                   LogLevel::value level,
                   Formatter::ptr &formatter,
                   std::vector<LogSink::ptr> &sinks) : Logger(logger_name, level, formatter, sinks) {}

    protected:
        // 同步日志器，将日志直接通过落地模块句柄进行日志落地
        void log(const char *data, size_t len)
        {
            std::unique_lock<std::mutex> lock(_mutex);
            if (_sinks.empty())
            {
                return;
            }
            for (auto &sink : _sinks)
            {
                sink->log(data, len);
            }
        }
    };

    class AsyncLogger : public Logger
    {
    public:
        AsyncLogger(const std::string &logger_name,
                    LogLevel::value level,
                    Formatter::ptr &formatter,
                    std::vector<LogSink::ptr> &sinks,
                    AsyncType looper_type) : Logger(logger_name, level, formatter, sinks),
                                             _looper(std::make_shared<AsyncLooper>(std::bind(&AsyncLogger::realLog, this, std::placeholders::_1), looper_type)) {}
        void log(const char *data, size_t len)
        {
            _looper->push(data, len);
        }
        void realLog(Buffer &buf)
        {
            if (_sinks.empty())
            {
                return;
            }
            for (auto &sink : _sinks)
            {
                sink->log(buf.begin(), buf.reabAbleSize());
            }
        }

    private:
        AsyncLooper::ptr _looper;
    };
    enum class LoggerType
    {
        LOGGER_SYNC,
        LOGGER_ASYNC
    };
    // 使用建造者模式来建造日志器，不涉及hi我让使用者直接构造，简化操作
    // 1.抽象一个日志器建造者类（完成日志器对象所需零部件的构建&日志器的构建）
    class LoggerBuilder
    {
    public:
        LoggerBuilder() : _logger_type(LoggerType::LOGGER_SYNC),
                          _limit_level(LogLevel::value::DEBUG),
                          _looper_type(AsyncType::ASYNC_SAFE) {}

        void buildloggerType(LoggerType type) { _logger_type = type; }
        void buildEnableUnSafeAsync() { _looper_type = AsyncType::ASYNC_UNSAFE; }

        void buildLoggerName(const std::string &name) { _logger_name = name; }
        void buildLoggerLevel(LogLevel::value level) { _limit_level = level; }
        void buildFormtter(const std::string &patern)
        {
            _formatter = std::make_shared<Formatter>(patern);
        }
        template <typename SinkType, typename... Args>
        void buildSink(Args &&...args)
        {
            LogSink::ptr psink = SinkFactory::create<SinkType>(std::forward<Args>(args)...);
            _sinks.push_back(psink);
        }
        virtual Logger::ptr build() = 0;

    protected:
        AsyncType _looper_type;
        LoggerType _logger_type;
        std::string _logger_name;
        LogLevel::value _limit_level;
        Formatter::ptr _formatter;
        std::vector<LogSink::ptr> _sinks;
    };

    // 2.派生出具体的建造者类--局部日志器的建造者类和全局日志器的建造者类
    class LocalLoggerBuilder : public LoggerBuilder
    {
    public:
        Logger::ptr build() override
        {
            assert(_logger_name.empty());
            if (_formatter.get() == nullptr)
            {
                _formatter = std::make_shared<Formatter>();
            }
            if (_sinks.empty())
            {
                buildSink<StdoutSink>();
            }
            if (_logger_type == LoggerType::LOGGER_ASYNC)
            {
                return std::make_shared<AsyncLogger>(_logger_name, _limit_level, _formatter, _sinks, _looper_type);
            }
            // 否则返回一个同步日志器
            return std::make_shared<SyncLogger>(_logger_name, _limit_level, _formatter, _sinks);
        }
    };
    class LoggerManager
    {
        public:
            static LoggerManager& getInstance()
            {
                static LoggerManager eton;
                return eton;
            }
            void addGogger(Logger::ptr &logger)
            {
                if(hasLogger(logger->name()))
                {
                    return;
                }
                std::unique_lock<std::mutex> lock(_mutex);
                _loggers.insert(std::make_pair(logger->name(),logger));
            }
            bool hasLogger(const std::string &name)
            {
                std::unique_lock<std::mutex> lock(_mutex);
                auto it=_loggers.find(name);
                if(it==_loggers.end())
                {
                    return false;
                }
                return true;
            }
            Logger::ptr getLogger(const std::string &name)
            {
                std::unique_lock<std::mutex> lock(_mutex);
                auto it=_loggers.find(name);
                if(it==_loggers.end())
                {
                    return Logger::ptr();
                }
                return it->second;
            }
            Logger::ptr rootLogger()
            {
                return _root_logger;
            }
        private:
            LoggerManager()
            {
                std::unique_ptr<bitlog::LoggerBuilder> builder(new bitlog::LocalLoggerBuilder());
                builder->buildLoggerName("root");
                _root_logger=builder->build();
                _loggers.insert(std::make_pair("root",_root_logger));
            }
        private:
            std::mutex _mutex;
            Logger::ptr _root_logger;//默认日志器
            std::unordered_map<std::string,Logger::ptr> _loggers;

    };
    //设计一个全局日志器的建造者，在局部的基础上增加--将日志器提交的单例对象中
    class GlobalLoggerBuilder : public LoggerBuilder
    {
    public:
        Logger::ptr build() override
        {
            assert(_logger_name.empty());
            if (_formatter.get() == nullptr)
            {
                _formatter = std::make_shared<Formatter>();
            }
            if (_sinks.empty())
            {
                buildSink<StdoutSink>();
            }
            Logger::ptr logger;

            if (_logger_type == LoggerType::LOGGER_ASYNC)
            {
                logger=std::make_shared<AsyncLogger>(_logger_name, _limit_level, _formatter, _sinks, _looper_type);
            }else{
                logger=std::make_shared<SyncLogger>(_logger_name, _limit_level, _formatter, _sinks);
            }
            // 否则返回一个同步日志器
            LoggerManager::getInstance().addGogger(logger);
            return logger;
        }
    };
}

#endif